Consider the following data that represents a random sample
Consider the following data that represents a random sample out of a very large population:
0.43, 4.89, 5.29, 5.16, 0.59, 7.50, 4.48, 6.22
Regardless of your answer to (a), assume the population distribution is normal and use that fact to
create a 90% CI for µ.
Solution
Note that
Lower Bound = X - z(alpha/2) * s / sqrt(n)
Upper Bound = X + z(alpha/2) * s / sqrt(n)
where
alpha/2 = (1 - confidence level)/2 = 0.05
X = sample mean = 4.32
z(alpha/2) = critical z for the confidence interval = 1.644853627
s = sample standard deviation = 2.528816776
n = sample size = 8
Thus,
Lower bound = 2.849382847
Upper bound = 5.790617153
Thus, the confidence interval is
( 2.849382847 , 5.790617153 ) [ANSWER]
